- 1. How does O2get in and out?
- a. Pig- The pig gets oxygen just like we do. It breathes in air through its mouth to its lungs. Its lungs convert the air and it breathes out carbon dioxide.
- b. Crayfish- The crayfish has gills just like a fish. It gets the oxygen out of the water.
- c. The starfish gets oxygen through a completely different way. It gets oxygen from diffusion that enters through the tubed feets.
- 2. How is O2and other materials moved throughout the body?
- a. Pig- First it breathes in and the oxygen goes to the lungs. Its is then pumped into the blood stream and taken to the vital organs.
- b. Crayfish- It gets oxygen through it gills, they have an open circulatory system which means that there is no difference between blood and other fluids in the body. That is how it gets oxygen and other materials through the body
- c. Starfish- they have a unique way of circulating materials. The use a kind called water vascular system. They filter the water with a series of ducts for gas exchange, feeding, movement, and waste removal.
- 3. Draw a diagram of the movement of O2 and other materials through this system (or take a picture and mark up the movement).
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| Pig |
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| Crayfish |
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| Starfish |